U.S. Pat. No. 3,348,732 issued 24 Oct. 1967 to Heinz SCHWARZ, shows that is it known to provide an article dispensing device carried over a horizontal tray, for sliding displacement of a commodity unit over the tray through actuation of a slider block. The slider block is carried transversely of a transport bar, which can be pulled by a coupling member at the outer end of the transport bar. The inner end of the transport bar is slidingly mounted by an angle piece to a horizontal guide track, which is anchored at both ends to the stationary main frame of the dispensing device.
Such known article dispensing devices are useful in view of stacking or "grouping" scattered commodity units remaining in a partially depleted row of commodity units in a display counter, or alternately, in view of unloading these remaining commodity units from the display counter into a loading container in the walk-through alley for the customer. However, for inventory control purposes, it is time-consuming and error-prone to compute--by visual inspection--the number of remaining commodity units in the row, by counting each and every such commodity unit on display.